This Medicare Part D data spotlight finds prices for some commonly used brand-name drugs rising in 2010 for beneficiaries who reach the coverage gap (or “doughnut hole”), with increases since 2006 far exceeding the growth in inflation.

The Part D benefit’s coverage gap generally requires enrollees to pay the full cost of their drugs after their total drug spending exceeds their initial coverage limit ($2,830 in 2010) until they reach the threshold for receiving catastrophic coverage ($6,440 in 2010). In 2007, an estimated 3.4 million Part D enrollees reached the coverage gap.

Using data posted on the government’s Medicare.gov website, the analysis looks at prices for commonly used brand-name drugs without a generic substitute for enrollees in stand-alone prescription drug plans. The prices reflect the amount that enrollees would pay for a 30-day supply after they reach the coverage gap and before catastrophic coverage begins.

This data spotlight is one in a series analyzing key aspects of the Medicare Part D drug plans that will be available to beneficiaries in 2010. The analysis was conducted jointed by Jack Hoadley and Laura Summer of Georgetown University, Elizabeth Hargrave of NORC at the University of Chicago, and Juliette Cubanski and Tricia Neuman of the Kaiser Family Foundation.